A massive sunstorm on 4th August 1972 may have scuppered a major US Navy operation in Vietnam by exploding hundreds of mines.

Operation Pocket Money, a plan to deploy 11,000 sea mines off the coast of North Vietnam to cut off naval supply routes to the region, was hit by the detonation of dozens of mines in a strange event.

Now, a new study says extreme space weather could have caused the explosions south of Hai Phong, North Vietnam.

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A new Boulder study claims Operation Pocket Money, a plan to deploy 11,000 sea mines off the coast of North Vietnam to cut off naval supply routes to the region, was scuppered by the 1972 storm. Pictured, footage from the big Bear Observatory of the August 7th flare that was part of the same eruption

THE 1972 SOLAR STORM

The major solar flare that erupted on Aug. 4, 1972 knocked out long-distance phone communication across some states, including Illinois, according to a NASA account.

‘That event, in fact, caused AT&T to redesign its power system for transatlantic cables,’ NASA wrote in the account.

One of the flares was a ‘two-ribbon’ flare, dubbed the ‘seahorse flare’ in which the flaring region appear as two bright lines threading through the area between sunspots within a sunspot group.

Researchers say the solar storm activated magnetic sensors in the undersea destructor mines, causing them to blow up en masse.

The underwater explosives were rigged to detonate in response to magnetic, acoustic, and pressure signatures from passing ships.

However, on August 4, 1972, crew members aboard U.S. Task Force 77 aircraft suddenly observed explosions south of Hai Phong.

20 to 30 explosions were documented in just 30 seconds.

Another 25 to 30 patches of muddy water were also observed, indicative of further explosions.

‘The extreme space weather events of early August 1972 had significant impact on the US Navy, which have not been widely reported,’ researchers led by Delores Knipp, a space weather expert at the University of Colorado at Boulder, said in their paper.

‘These effects, long buried in the Vietnam War archives, add credence to the severity of the storm: a nearly instantaneous, unintended detonation of dozens of sea mines south of Hai Phong, North Vietnam on 4 August 1972.’

The largest solar storm ever recorded, The Carrington Event in 1859, took out telegraph machines across the US, purportedly causing sparks to fly from equipment – some bad enough to set fires inside offices.

Another 25 to 30 patches of muddy water were also observed, indicative of further explosions.

Additional mining missions began on 11 May.

By the end of the year Navy and Marine Corps bombers had dropped more than eight thousand mines in North Vietnamese coastal waters and three thousand in inland waterways

The team concluded that the 1972 event could have been in the same league as the Carrington Event.

‘The activity fits the description of a Carrington‐class storm minus the low latitude aurora reported in 1859,’ they wrote.

U.S. Marine helicopters leave troops into suspected Viet Cong area during a full fledged assault operation by U.S. Marines near Da Nang, South Vietnam, in this April 29, 1965 black-and-white file photo during the Vietnam War. Researchers now say a solar storm may have impacted the US Navy during a mining operation

‘In our view this storm deserves a scientific revisit as a grand challenge for the space weather community, as it provides space‐age terrestrial observations of what was likely a Carrington‐class storm,’ the authors said.

NASA describes the storm as ‘legendary’ because it occurred in between two Apollo missions: the crew of Apollo 16 had returned to Earth in April and the crew of Apollo 17 was preparing for a moon landing in December.

A new Boulder study claims Operation Pocket Money, a plan to deploy 11,000 sea mines off the coast of North Vietnam to cut off naval supply routes to the region, was scuppered by the storm. Pictured, a solar flare erupting in 2013.

It says a moonwalker caught in the August 1972 storm might have absorbed dangerous levels of radiation, forcing them to return to Earth immediately for treatment.

The US Navy attributed the dramatic event to ‘magnetic perturbations of solar storms.’

WHAT ARE SOLAR STORMS AND ARE THEY DANGEROUS?

Solar storms, or solar activity, can be divided into four main components that can have impacts on Earth:

Solar flares: A large explosion in the sun’s atmosphere. These flares are made of photons that travel out directly from the flare site. Solar flares impact Earth only when they occur on the side of the sun facing Earth.

Coronal Mass Ejections (CME’s): Large clouds of plasma and magnetic field that erupt from the sun. These clouds can erupt in any direction, and then continue on in that direction, plowing through solar wind. These clouds only cause impacts to Earth when they’re aimed at Earth.

High-speed solar wind streams: These come from coronal holes on the sun, which form anywhere on the sun and usually only when they are closer to the solar equator do the winds impact Earth.

Solar energetic particles: High-energy charged particles thought to be released primarily by shocks formed at the front of coronal mass ejections and solar flares. When a CME cloud plows through solar wind, solar energetic particles can be produced and because they are charged, they follow the magnetic field lines between the Sun and Earth. Only charged particles that follow magnetic field lines that intersect Earth will have an impact.

While these may seem dangerous, astronauts are not in immediate danger of these phenomena because of the relatively low orbit of manned missions.

However, they do have to be concerned about cumulative exposure during space walks.

This photo shows the sun’s coronal holes in an x-ray image. The outer solar atmosphere, the corona, is structured by strong magnetic fields, which when closed can cause the atmosphere to suddenly and violently release bubbles or tongues of gas and magnetic fields called coronal mass ejections

The damage caused by solar storms

Solar flares can damage satellites and have an enormous financial cost.

The charged particles can also threaten airlines by disturbing Earth’s magnetic field.

Very large flares can even create currents within electricity grids and knock out energy supplies.